diff --git a/action.yml b/action.yml
index a9bdf25..193472f 100644
--- a/action.yml
+++ b/action.yml
@@ -29,6 +29,9 @@ inputs:
   version:
     description: Explicitly set the version here instead of automatically detecting from `package.json`. Useful for non-JavaScript projects where version may be output by a previous action.
     required: false
+  regex_pattern:
+    description: An optional attribute containing the regular expression used to extract the version number.
+    required: false
 outputs:
   tagname:
     description: Returns the new tag value. Empty if a tag is not created.
diff --git a/app/main.js b/app/main.js
index 05b6b51..a12a94c 100644
--- a/app/main.js
+++ b/app/main.js
@@ -32,7 +32,7 @@ async function run () {
         break
 
       case 'regex':
-        version = (new Regex(root, new RegExp(pattern, 'i'))).version
+        version = (new Regex(root, new RegExp(core.getInput('regex_pattern', { required: true }), 'i'))).version
         break
 
       default: